Tuning VE Tables Megasquirt

[Challenger]

I was able to get a good portion of my VE table in the right range but looking at my megalog I can tell my VE without EGO correction wouldnt be producing my target AFRs. I assume thats what I want to aim for.

 

Seems like I should have tuned for longer by watching my AFR and then adjusting the VE till I get to the AFR I want. Once that is done, go into your AFR table and put in the AFR you had been trying to achieve. At that point you can turn on EGO correction and in theory the engine shouldnt run differently since target AFR are what the VE produces.

 

I was looking at a log of a drive and it seems like you can see the actual AFR move towards the target AFR fairly quickly, is there a way to look at what the instantaneous AFR correction is? That way I could look at the log and see where my VE tables need to be richened or leaned out. I assume this is exactly what tunerstudio's VE analyze live does?

 

Thanks

 

Heres some incentive to help, drove it a wopping 7 miles today! Thats the furthest its been in YEARS!

 

Edited April 29, 2012 by Challenger

[dexter72]

Enjoy, Tuning is fun. Wait till you get it real close.

[Noddle]

Enjoy, Tuning is fun. Wait till you get it real close.

 

I know on my dash board ( tuner studio ) I have a AFR correction gauge, so there it is recorded, I'm not sure what it's call, since I not at home.

[Tennesseejed]

You can tune your VE tables a couple of ways:

 

1. With EGO on, take a long drive/datalog. Using the VE Analyze feature in MegaLogViewer, you can adjust and modify your current VE table. Make several runs and use a little common sense to smooth out cells that don't match neighboring cells. After half a dozen datalogs, you can get a pretty good tune.

 

2. Purchase a registered version of TunerStudio and run VE Analyze Live while driving. The program will (I think) automatically burn adjusted tables periodically, but you should certainly hit the "burn" button before closing the program. I normally raise the EGO correction to 5% with a new/rough tune and then lower back to 1% after a few runs.

 

Keep in mind that your AFR table is most important. Spend some time studying different AFR tables as well as studying how your particular engine operates, i.e., at what MAP/RPM does it idle and cruise on the highway. Highway cruising at 11.5:1, for example, is a waste of gas and performance.

 

Without dyno tuning, you really don't know for certain the best AFR for max power and torque, but you can get a pretty good idea by studying different tunes.

 

Lastly, I love your car. Those black wheel are sweet.

[Challenger]

Thanks for the input. Well I think my VE tables are pretty good for how much I have done. I definitely need to study more on AFR maps to further tune my VE tables. I will be getting the full version at some point soon hopefully. Id like to get it closer before I spend the money for it.

 

So I started looking at my EGO settings and what is everyone using for the constraints as far as MAP, TPS and coolant? Right now my coolant is set to 160 degrees which it barely reaches right now. On warmer days I assume Ill have no problem getting past that.

 

 

Im kind of concerned with the controller authority and MAP settings. Right now its not doing anything for boost... good thing my VE puts me at like 11:1 in boost.

 

Also, I have my base AFR table I have been using and its only for <100kPa. Is there anyway to keep my AFRs and just extend the table up into boost?

Edited May 1, 2012 by Challenger

[Tennesseejed]

You're using a narrowband O2 sensor? I don't know if you can tune effectively with a narrowband.

 

EGO active above 160 is good, but double check to see if any warmup enrichments extend beyond 160F. If so, EGO might be fighting with those.

 

If you have trouble with smooth idle, you can also drop your "active above" down to 600RPM or so. This works particularly well with Analyze Live.

 

I think controller authority of 15% might be a little high. What you are doing is allowing large corrections instead of small, incremental corrections. I think the manual says a high authority value is good for a rough tune, but once you have a pretty good tune, a high controller authority might result in overcorrection.

 

FWIW, I though installing MS was the easy part. Certainly the more challenging part is the tune. Hang in there. It can be frustrating, but in the end it's pretty rewarding.

 

Last couple of thoughts: Try to manage you tunes in an organized fashion. You'll probably have 10 or more soon enough. Change one thing at a time and save the old tune so you can revert back if you mess up. Also, if your like me, you'll be tweaking your tune almost constantly for months. And then, as soon as you think its good enough, a week later you'll start fussing around again. Constant tuning kinds takes away from just enjoying driving the car. Once its good enough, try to leave it along for awhile.

 

Good luck.

[Challenger]

Im using a wideband, I cant imagine doing this with a narrowband. haha Enrichments end at 160. Thats another reason I havent been able to tune much more, my car is intercooled, oil cooler, 160 thermostat and no hood. Car wont even get out of WUE if Im driving it moderately. Im hoping with the hood and my radiator ducting it will be better. Might have to go up to a 190 thermostat.

 

Yeah I am gonna set up some sort of way to organize and categorize tunes and data logs.

 

Little update, tuning is gonna be put on hold for awhile. Ive been driving around up till last night on just a downpipe and now I only have about 7-8 ft of 3 inch straight pipe. (not done haha) Anyways I took the car to show my grandpa and my dad called and said there was a cop in front of our house for an hour waiting for me to come back. I do not doubt my car has been annoying but Ive tried to keep it going around speed limits since I live in a residential area across from a school. Anyways, 25 in first is plenty loud and sounds like Im speed so I imagine someone thought I was speeding.. Oh well, my car isnt a 100% legal so Ill need to get some stuff figured out before I drive it more.

 

Thanks

Edited May 2, 2012 by Challenger

[Challenger]

Alright, got the registered version of tuner studio and megalog viewer. Nice package.

 

So it was pretty cool to watch it change VE values as I went... so much better than the trial and error method.

 

Do I still leave EGO correction on while running VE analyze? Should it be the 5% or so while doing the autotune? I think I have it at 6% now.

 

Im still working with it but I did notice the AFRs were not matching up exactly when just sitting and idling. Seems like it was half an AFR or so off, is that close enough?

 

Working on getting organized as well. Saving my tunes as I go and making notes in the same folder for each iteration and what was changed and where it came from (eg. Tune1.3 comes from Tune1.2, etc)

 

Im getting to the point where I can "safely" get into boost, or so I think. Ill have to restrain myself some, I got up to about 9 psi or so with good AFRs... it felt like a rocket ship! haha

Edited May 10, 2012 by Challenger